aFaculty of Pharmacy and Pharmaceutical
Sciences,bDepartment of Biochemistry University of Alberta Edmonton, AB, Canada

Abstract:
A computer program has been developed to accurately and automatically
predict the 1H and 13C chemical shifts of unassigned
proteins on the basis of sequence homology. The program (called SHIFTY)
uses standard sequence alignment techniques to compare the sequence of
an unassignedprotein against the BioMagResBank
a public database containing sequences and NMR chemical shifts of nearly
200 assigned proteins [Seavey et al. (1991) J. Biomol. NMR, 1, 217-236
PubMed PMID: 1841696].
From this initial sequence alignment,
the program uses a simple set of rules to directly assign or transfera complete set of 1H or 13C
chemical shifts (from the previously assigned homologues) to the unassigned
protein. This " homologous assignment"protocol takes advantage of the simple
fact that homologous proteins tend to share both structural similarity
and chemical shift similarity. SHIFTY has beenextensively tested on more than 25 medium-sized
proteins. Under favorable circumstances, this program can predict the 1H
or 13C chemical shifts ofproteins with an accuracy far exceeding
any other method published to date. With the exponential growth in
the number of assigned proteins appearing inthe literature (now at a rate of more
than 150 per year), we believe that SHIFTY may have widespread utility
in assigning individual members infamilies of related proteins, an endeavor
that accounts for a growing portion of the protein NMR work being done
today.

Listed here are the proteins
used for this article. Information in the table includes chemical
shifts, X-ray structure, the accession codes for data deposited in
the BMRB and PDB databases, the resolution at which the crystal structure
was solved, the sequence homologues that were used, the correlation coefficients
for the different NMR specs, and the assignment prediction accuracy.